From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50119) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cBH2L-00070i-Ct for qemu-devel@nongnu.org; Mon, 28 Nov 2016 03:11:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cBH2I-0004Ye-6N for qemu-devel@nongnu.org; Mon, 28 Nov 2016 03:11:41 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:33150 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cBH2I-0004YN-1s for qemu-devel@nongnu.org; Mon, 28 Nov 2016 03:11:38 -0500 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uAS89MPI030378 for ; Mon, 28 Nov 2016 03:11:37 -0500 Received: from e37.co.us.ibm.com (e37.co.us.ibm.com [32.97.110.158]) by mx0b-001b2d01.pphosted.com with ESMTP id 270f5jchmw-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 28 Nov 2016 03:11:37 -0500 Received: from localhost by e37.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 28 Nov 2016 01:11:36 -0700 References: <20161126054650.4486-1-haoqf@linux.vnet.ibm.com> <20161126054650.4486-2-haoqf@linux.vnet.ibm.com> From: Hao QingFeng Date: Mon, 28 Nov 2016 16:11:29 +0800 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Message-Id: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v2 1/1] block/vmdk: Fix the endian problem of buf_len and lba List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: liujing , qemu-devel@nongnu.org, qemu-block@nongnu.org Cc: borntraeger@de.ibm.com, cornelia.huck@de.ibm.com, kwolf@redhat.com, qemu-stable@nongnu.org =E5=9C=A8 2016-11-28 15:56, liujing =E5=86=99=E9=81=93: > Hi QingFeng, > > > I just have a question that whether the marker->data > need convert? > > I've no idea, just suddenly realized this question. > nope, the data is type of char * for the compressed data stream, so no=20 endian issue. thanks. > Jing > > On 11/26/2016 01:46 PM, QingFeng Hao wrote: >> The problem was triggered by qemu-iotests case 055. It failed when it >> was comparing the compressed vmdk image with original test.img. >> >> The cause is that buf_len in vmdk_write_extent wasn't converted to >> little-endian before it was stored to disk. But later vmdk_read_extent >> read it and converted it from little-endian to cpu endian. >> If the cpu is big-endian like s390, the problem will happen and >> the data length read by vmdk_read_extent will become invalid! >> The fix is to add the conversion in vmdk_write_extent, meanwhile, >> repair the endianness problem of lba field which shall also be convert= ed >> to little-endian before storing to disk. >> >> Cc: qemu-stable@nongnu.org >> Signed-off-by: QingFeng Hao >> Signed-off-by: Jing Liu >> Signed-off-by: Kevin Wolf >> --- >> block/vmdk.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/block/vmdk.c b/block/vmdk.c >> index a11c27a..26e5f95 100644 >> --- a/block/vmdk.c >> +++ b/block/vmdk.c >> @@ -1354,8 +1354,8 @@ static int vmdk_write_extent(VmdkExtent=20 >> *extent, int64_t cluster_offset, >> goto out; >> } >> >> - data->lba =3D offset >> BDRV_SECTOR_BITS; >> - data->size =3D buf_len; >> + data->lba =3D cpu_to_le64(offset >> BDRV_SECTOR_BITS); >> + data->size =3D cpu_to_le32(buf_len); >> >> n_bytes =3D buf_len + sizeof(VmdkGrainMarker); >> iov =3D (struct iovec) { > --=20 QingFeng Hao(Robin)